The sentences have the same basic meaning, but "ever" implies "sometimes, on occasion". The difference in meaning is very slight. In fact, the difference is approximately that of "Do you eat pizza for breakfast?" and "Do you sometimes eat pizza for breakfast?"

I do not know if they still exist, but 10-15 years ago I used to eat "breakfast pizzas" with eggs, bacon or sausage, etc. They came frozen and could be heated in a microwave oven. So, yes, I ate pizza for breakfast.